Satellite communication systems have used phased array antennas to communicate with multiple users through multiple antenna beams. Typically efficient bandwidth modulation techniques are combined with multiple access techniques and frequency separation methods are employed to increase the number of users. However, with the electronic environment becoming increasingly dense with the proliferation of wireless personal communication devices such as cellular telephones and pagers, even more information and sophistication are required for these wireless communication systems. For example, with all the users competing for the limited frequency spectrum, the mitigation of interference between the various systems is a key to the allocation in the spectrum to the various systems.
Furthermore, the concept of spectral sharing, e.g., the ability of multiple systems to simultaneously use common spectrum, is of major importance to governmental bodies such as the Federal Communications Commission (FCC) granting communication licenses to satellite system operators.
Thus what is needed is a communication system that mitigates interference between other systems while sharing spectrum with those other systems. Thus, what is also needed are an apparatus and method that can share and provide for the sharing spectrum with other communication systems.
Although a variety of techniques for beam forming have been developed, current digital beam forming antenna systems lack the computational performance required by many communication system applications. Consequently, there is a need for a digital beam forming system that provides high-performance computational power at low cost.